A link member which is attached such that the link member can freely rotate or rock is widely used to support a member or deliver a load. For example, in a vehicle, the link member is incorporated into a vehicle suspension mechanism. The vehicle suspension mechanism includes an arm member such as a trailing arm, and a suspension arm, and a collar member having a hollow cylindrical shape which pivotally supports the arm member in a vehicle body is joined to the arm member. A bush is press-fitted into the collar member, arid a hollow shaft inserted, into the bush is connected to a bracket and the like from a vehicle body side. Examples of the collar member include a rolled collar formed in a cylindrical shape by rolling a strip-shaped plate material (for example, see Patent Literature 1).